Functional MRI, Diffusion Tensor Imaging, Magnetic Source Imaging and Intraoperative Neuromonitoring Guided Brain Tumor Resection in Awake and Under General Anaesthesia

Neuroimaging has evolved from Computed Tomography (CT), CT-Positron Emission Tomography (CT-PET) and Magnetic Resonance Imaging (MRI) scanner in 1970s and 1980s to functional MRI (fMRI), Diffusion Tensor Imaging (DTI) and Magnetic Source Imaging (MSI) or Magnetoencephalography-MRI (MEG-MRI) fusion in 1990s and 2000s. Anatomical and functional neuroimages are currently regarded by most as vital in planning for brain tumors surgery. These anatomical and functional neuroimages can be fused and exported to the neuronavigation system in the operating theatre (Figure 1). Collectively, these images are known as extraoperative neuroimages. On the contrary, intraoperative neuroimages are images that obtained intraoperatively and can be exported regularly to the navigation system. The intraoperative images can be obtained by using either intraoperative CT (iCT), MRI (iMRI) or ultrasound [3D-iUS) [1-3]. Safer and successful brain tumors surgery requires not only neuroimages-guided surgery but also properly defined the eloquent (important and function‐ al) cortices and monitoring of the vital areas of the brain and other organs. Awake surgery with intraoperative brain mapping, and surgery under general anaesthesia with intraoperative monitoring (IOM) which are guided by neuroimages are two operative techniques for brain tumors that are currently regarded by most as gold standard [4-8]. This chapter describes the current functional neuroimaging modalities (fMRI, DTI and MSI), brain mapping, surgery